Closure for pressure cookers



P. W. STEPHENS vCLOSURE FOR PRESSURE COOKERS Filed Dec. so, 1936 2 Sheets-Shed l UNITED STATES PATENT OFFICE I I mm: roa i i gs una oooxnns Application Nil. 118,4.1

This invention relates to pressure cookers, and tion illustrated herewith a pressure cooker is more particularly to improved closure and handle shown having a body portion III and a cover H. means therefor. The cover II has thereon a pressure gauge l2 The present application is a continuation in or standard type, a relief valve II, and a handle 5 part of an application bearing Serial No. 89,189 or knob ll of heat insulating material. The 5 and heretofore filed on July 6, 1936. cover H is provided with a channelled periph- One feature of this invention is that it proeral portion l5 having therein an annular gasvides a one piece positively operated closure band ket l6 adapted to contact the lip or upper edge for sealing the cover to the body portion of the ll of the body portion III of the cooker.

10 cooker; another feature of this invention is that Closure means IB- is provided for clamping 10 yielding means is provided through which the the cover into sealing engagement with theedge sealing. tension of the band is exerted; yet an- H, this closure means comprising a flexible other feature is that this yielding means is a metal band I 9 having fastened thereto closure coil spring so arranged that breakage thereof segments 20 having a top flange 2| and a botl5 does not destroy the seal between the cover and tom flange 22. It will be noted that the top the body portion of the cooker; still another feaflange 2| diverges downward from the plane ture of this invention is that the spring is of the band at a slight angle. and that the botsheathed when the band is in sealing position; tom flange 22 diverges substantially from the a further feature of this invention is a handle plane of the band being here shown at an angle so arranged as to be fastened to the cooker at of about forty-five degrees with such plane. 20 a point where no pressure differential exists; The upper part of the body portion I0, as will other features and advantages of this invention be best seen in Fig. 4, is provided with an outwill be apparent from the following speciflcawardly and downwardly turned curl having the tion and the drawings, in which: upper substantially horizontal portion I l and Figure 1 is a top plan view of such a cooker; a downwardly turned portion 23 spaced from the 25 Fig. 2 is a fragmentary view of the same cooker, body portion I0. It will be'noted that this downpartly in section; Fig. 3 is a side elevation of the wardly turned portion is rolled back on itself, cooker; and Fig. 4 is avertical fragmentary secas by a curling die, to provide a substantially tional view along the line 44 of Fig. 1. rigid'annular peripheral roll or bead 24 adapted In order to make an operative pressure cooker to be engaged by the angularly disposed surface 30 some means must be provided for clamping the of the bottom flange 22. cover to the body portion of the cooker to efiect The flexible band l9 has two ends 25 and 26 a seal therebetween sumcient to maintain the normally adjacent or not substantially separated desired pressure in the cooker. This invention from each other. The ends of the flexible band 5 provides a closure or clamping means positively 19 are adapted to be drawn toge he or separated operable for clamping or disengaging, the whole to vary the efiective diameter of the closure so arranged that a single movement effects a. member, by the action of toggle means compristight seal all the way around the periphery of ing a base 2'! of an operating lever 28 and a conthe cover. In order to insure a seal of suiiicient necting link 29. One end of the base 21 of the pressure despite variations in gasket thickness, operating lever is connected to the end 25 of the 40 wear of parts, and the like, the closure is proflexible band i9 as by a pivot 30; one end of vided with yielding spring means through which the link 29 is operatively connected to the end the closing pressure is exerted. Differences in 26 of the band; and the base 7 f the lever the eifective diameter of the closure band necand the link 29 are Pivotally c ed together essary for proper sealing are absorbed in thisat a po nt Movement of the level 28 thus 45 spring. actuates the toggle means to vary the separation The cooker is also provided with an improved of the ends .and thus the effective diameter of handle which is so constructed and located with the closure band, either drawing it together to respect to the body of the cooker that the rivet clamp the cover onto the body portion of the or other fastening means does not have to extend cooker or expanding the band to enable it to be 50 through a portion of the cooker where a pressure conveniently removed from closure relationship differential exists. The handle also serves to 'rewith the cooker. inforce the downwardly turned curl against Referring again to Fig. 4, it will be seen that, which the closure band exerts its pressure. contraction of the band by the toggle means re- In the particular embodiment of this invensults, through the interaction oi the bead 24 and 55 slight downward angle to the planeof' the band,

as described above, and thus the sealing pressure on the cover is effected at a point substantially central to the gasket l6 rather than near the outer edge thereof. The cover H has an opening 32 therethrough in which a tube 33 is mounted. Valve means is provided for closing the upper end of this tube, here shown as a valve body having a central aperture 34 adapted to engage the tube 33 and a cone-shaped valve member 35 adapted to project down into and close the top of the tube 33. The valve body is preferably provided with a handle 36 of heat insulating material, enabling it to be conveniently removed when the cooker is hot. The internal diameter of the tube 33 and the weight of the valve are so proportioned that pressures within the'cooker up and to the desired maximum will not lift the valve member 35 from its seat in the top of the tube, but higher pressures will lift it and thus vent the vapor pressure existing within the cooker.

The lever 28 which operates the toggle means is provided with an upturned portion 36 adapted to abut the tube 33 and to be engaged by the valve when the lever 28 is in closed orclamping position and the valve is in sealing position. To close the cooker the cover is placed in position, the closure band placed around it inthe proper plane, and the lever 28 moved into the position shown in Fig. 1 to draw the ends of the metal band It! together and thusclamp the cover onto the body portion of the cooker. When the lever is' in closed position with the upturned portion -3B abutting the tube 33, the valve, is placed over the tube and the lever 28 is thus locked in closed position. Before the closure means can. be loosened to remove the cover, therefore, the valve must be removed to vent any pressure within the cooker.

Referring more particularly to Figs. 1 and 2, it will be seen that the end 26 of the band I9 is turned back on itself to form a socket 31, closed on two sides and at the ends thereof. A coil spring 38 is mounted in the socket abutting the forward end, where it is held in position by a rivet or pin 39. It will be understood that any yielding or resilient means may be used, although a coil spring is preferable. The end of the link 29 is slidably splincd in the socket at the other end of the spring 38, here shown as comprising a block 40 lying within the socket and a pivot pin 4i connecting the link 29 to the block. The link 29 has wing portions 42 and 43 which lie above and below the socket when the band is in closed or sealing position, thus sheathing the spring. This feature prevents an undesirable deposit of grease, soot or the like from forming on the spring when the cooker is over a flame.

The presence of the spring 38 through which the closing tension of the toggle means is exerted on the band is very advantageous. It enables a positive toggle action to be used despite small differences in the effective diameter of the band when in sealing position. Such differences can arise from variation in tolerances in manufacturing, or from changes in the thickness of the gasket l6 during long continued use, and the like. The use of a coil spring mounted and arranged as shown enables easy' replacement of the spring should it break at any time. Moreover, the fact that it i.. a coil spring provides a safety feature in that breakage during use on'the cooker will not break the seal. That is, since the coil spring is sheathed in on all-four sides when the band is in sealing position breakage thereof merely results in a shift of the bandequivalent to the space existing between turns of the spring, and this is not sufllcient to break the seal and cause the loss of the pressure existing within the cooker.

Referring more particularly to Fig.4, it will be seen that the cooker is provided with a handle 44 having a portion 45 lying between the body portion l0 and the downwardly turned portion 23 thereof. The portion 45 is so constructed as to substantially fill the space between the body portion l0 and the downwardly turned portion and is arranged to be fastenedin place by means pass ing through the downwardly turned portion 2341 rather than the body portion of the cooker/W This means is here shown as: a screw 46. The

which does not, under constant usage, leak around the screw. The arrangement shown not only enables the screw to be placed through a portion where no pressure differential exists, but also serves to support the head 24 against which the flange '22 exerts pressure during use. It will be understood that any appropriate meansmay be used to fasten the handle in place which does not project through the body portion In into the inner part of the cooker.

While'l'have shown and described certain embodiments of my invention, it is to be understood that Changes, therefore, in the construction and arrangement maybe made without departing from the spirit-and scope of the invention as disposed in the-appended claims, in which it is my intention to claim all novelty inherent in myinvention as broadly as permissible, in view of the prior art.

I claim:

1. A closure device for sealing the cover to the body portion of a container, including: a substantially circular flexible metal band having flanges extending inwardly therefrom, at least one of said flanges diverging from the plane of said band, said band having two normally adjacent ends; a socket on one end of said band; a coil spring in said socket; and toggle means for positively varying the separation of said ends to vary the effective diameter of said band, said means having one end thereof slidably splined in said socket and in contact with said spring, whereby closing pressure is exerted through said spring.

, 2. A closure device for sealing the cover to the body portion of-a.container, including: a substantially circular flexible metal band having form a socket closed on two sides; a coil spring in said socket abutting the forward end thereof; and toggle means for positively varying the separation of said ends to vary the effective diameter, said toggle means having one end thereof slidably splined in said socket and abutting the it is capable of many modifications.

other end of said spring, whereby closing pressure is exerted through said spring.

3. Apparatus of the'character claimed in claim 2, wherein said toggle means has a portion thereof so formed as to sheath the open sides of said socket when said band is in sealing relation to said cover and body portion.

4. A container of the character described, ineluding: a body portion having an outwardly and downwardly turned peripheral curl at the top thereof; a cover adapted to form a closure for said container; a closure band having inwardly extending flanges, at least one of said flanges diverging from the plane of said band, one of said flanges being adapted to contact said cover and the other said curl, whereby contraction of said band seals said cover to said body portion; and a handle having a portion thereof lying between the body of said container and the downwardly turned portion of said curl, and a portion extendin; downwardly and outwardly therefrom.

5. Apparatus of the character claimed in claim 4, wherein said handle is fastened to the downwardly turned portion of said curl.

6. Apparatus of the character claimed in claim 4, wherein the portion of said handle lying between said body and said downwardly turned portion fills the entire space therebetween and is fastened to said downwardly turned portion b means extending therethrough. V

PERCY W. STEPHENS. 

